The report said that one analysis showed 55pc of paedophiles who possess indecent images also commit sexual offences against children.

Kate Fisher, a principal analyst at Ceop, said: "The images being downloaded are increasingly becoming more extreme, sadistic and violent and feature increasingly younger children."

However, the severity and number of images held by offenders are not enough alone to assess the risk they pose or the sentence they should receive, the report said.

Ceop urged police forces to prioritise the investigation of anyone caught with child abuse images who has easy access to children.

Andy Baker, deputy chief executive at Ceop, said: "It is clear that those who possess indecent images also pose a significant risk to children and understanding and managing that risk is not an easy undertaking.

"However, when we bring together the latest intelligence picture, nationally co-ordinated police action and operational support from our colleagues in the Serious Organised Crime Agency, we are making the UK a more hostile place for those who are seeking to exploit our children."

Ceop called for the authorities to look beyond the quantity and severity of the images, adding that a full risk assessment should be considered before a judge hands down any sentence.

Ms Fisher said the dramatic increase in images being downloaded, and the cuts to police resources, meant officers struggled with the workload but stressed that the notion that any case may result in the identification of a victim should be at the forefront of every investigation.

She added: "The levels of austerity and the caseload of indecent images of children is unprecedented. A quick and timely investigation for each case is increasingly unrealistic. Victim identification is the key element."

Almost 100 case studies from 34 forces found offenders who both possessed child abuse images and attacked children were "almost exclusively white males", most aged between 19 and 45.

One offender was found with 2.5 million still and moving images.

Mr Baker said: "This is an exceptional number of images but it does not necessarily mean that person will go on to commit contact offences."

Those not in work, and possibly therefore those with high levels of internet usage, those working in schools or care work, and those in manual and manufacturing jobs made up most of the sample, the report said.

In 85pc of cases, offenders looking at indecent images of children did so at home, with the rest looking at images mainly at work.

The majority lived with a spouse or partner and of that group, more than half were living with children.

From the 97 offenders in the study, 246 victims of contact abuse were identified.

Referrals to Ceop increased by 181pc between April last year and March, figures showed.

The report said: "This point in time has the potential to be a golden age for child protection, but the evolution of technology is likely to make the internet an increasingly difficult place to investigate.

"The predicted dramatic rise in work volumes will require a fresh look at policing priorities and the resources allocated to this area of policing."